The employment experiences of older workers play a central role in their transition from full-time labor force participants to fully retired individual. There are two sides to these experiences: (1) the decisions of the individuals ant heir households and (2) the decisions of the employers. The project exploits a recently established social data infrastructure initiative at the United States Census Bureau that permits the analysis, under appropriate confidentiality and privacy protocols, of longitudinal, matched employer-employee data. The research will study the effect on older workers of the dynamic interaction of workers and firms. The project will illustrate the utility of state unemployment insurance records, combined with Census administrative, business and demographic information, in the area of research on aging. The data will provide universal, longitudinal information on both workers and firms on a quarterly basis from 1990-1999. The research will begin with two states: Florida and Maryland, with the expectation of extending the analysis to California. Using unique linked data on firms and their workers the researchers will provide statistical answers to the following questions: (1) what types of firms employ older workers? (2) Does the likelihood of employing older workers vary by industry and firm characteristics? (3) How much persistence and heterogeneity is there in firm workforce composition? (4) How do firms adjust their workforce composition? (5) Who is hiring and firing older workers? (6) How are the earnings outcomes of older workers related to firm characteristics? (7) How does the changing nature of the firm affect older workers? (8) How does the earnings growth of older workers compare with the other workers within a firm hired at the same time? The research will explicitly model the age composition of employment in virtually all the economic entities in the targets states. These models will permit the researchers to describe the effects on older workers of the process of adjustment that business undertake when confronted with changes in the demand for their products or the quality of the available workforce.